Presentation on theme: "Rashmi Srivastava, MD Department of Child Health"— Presentation transcript:
1 Rashmi Srivastava, MD Department of Child Health Fever in Infants and Children: Sepsis, Meningitis, and Occult BacteremiaRashmi Srivastava, MDDepartment of Child Health
2 Fever PhobiaFever is the most common pediatric complaint, second only to routine care for clinic visits, and the most common reason kids are brought to the ER.In the Middle Ages, fever was felt to be a marker of death or divine punishment.Some feel true fever is harmful: 1/3 parents thought 38-40ºC( ºF), 2/ ºC( ºF), and all thought brain damage >41ºC(106ºF).5-20% have no localizing signs on PE with no history to explain the fever.The majority of kids with fever do not have a serious illness, although a small percentage harbor or may develop a serious bacterial infection.True fever is not harmful to a child if the fever is not due to a serious infection and the temperature elevation is not due to excess heat load, defective heat loss mechanism, CNS damage or disease, or excess heat production.
3 ‘True’ FeverOccurs when IL-1, IL-6, TNF-ά or other cytokines are released from monocytes and macrophages in response to infection, tissue injury, drugs, and other inflammatory processes, increasing the body’s set point. The anterior hypothalamus maintains an inherent set point near 36ºC(98.6ºF).Normal circadian rhythm, which is highest(up to 2ºC, 3ºF) ~6pm and lowest at 6am. This accounts for increased volume of ER visits that peaks in the evening. Most true fevers follow this diurnal pattern.
4 ‘False’ fever, aka hyperthermia Does not directly increase the body’s set point.CNS disease that directly affects the hypothalamus--ICH, infection.Diseases that increase the body’s production of heat--hyperthyroidism, malignant hyperthermia, salicylate overdose.Excess heat load--child left in a car or left next to a heater for too long.Defective heat loss mechanisms--burns, heat stroke, drugs that compromise blood flow and sweating mechanisms.Normal causes of temperature elevation include physical activity, ovulation, and environmental temperature.
5 Reliable Temperature Measurement All measurements are estimates of the body’s true core temp—central circulation=aorta and pulmonary artery.RECTAL—gold standardEsophageal—accurate but impracticalTactile and axillary—inaccurate, varies considerably with environmental temperatureTympanic—inaccurate in age <3 years
6 Benefits of feverThe hypothalamus will not allow the temp to rise above 41.5ºC(107ºF).WBCs work best and kill the most bacteria at 38-40ºC( ºF).Neutrophils make more superoxide anion, and there is more and increased activity of interferon.Coxsackie and polio virus replication is directly inhibited.
7 Fever without a source(FWS) 5 to 20% of febrile children have no localizing signs on PE and nothing in the history to explain the fever. By definition, less than 7 days.FWS(like fever) is most common in children younger than age 5, with a peak prevalence between 6 and 24 months of age.Those <6 months retain protective maternal antibodies against common organisms, while those months old are more immune competent, and are at a lower risk of developing bacteremia
8 Diagnostic Assessment in Children Age is important as 1) etiologic pathogens, 2) clinical exam, and 3) immune system capacity changes as the newborn ages.Most break them into the first 2-4 weeks of life(neonatal), 1-3 months, and 3 to 36 months.
9 NeonatalPE is felt to be unreliable in detecting many serious bacterial infections. Meningitis should always be considered—up to 10% appear well, only 15% have a bulging fontanelle, and 10-15% have nuchal rigidity. So, a high index of suspicion is important!!! ~20% will not have fever initially.Hyperthermia or hypothermiaLethargy or irritabilityPoor feeding or vomitingApneaDyspneaJaundiceHypotensionDiarrhea or abdominal distensionBulging fontanelleseizures
10 NeonatesThe majority of febrile neonates presenting to the ED have a nonspecific viral illness12% have serious bacterial infections (SBI)Infected by more virulent bacteriaMore likely to develop serious sequelae from viral infectionsGBBS is associated with high rates of meningitis(39%), non-meningeal foci(10%), and sepsis(7%)The most common bacterial infections are UTI and occult bacteremia
11 Neonatal Early Onset<7 Days Later Onset>7 Days Group B Strep E. ColiListeria MonocytogenesEnterobacteriaceaeEnterococcusStrep viridansStrep PneumoniaeHemophilus influenza ntHerpes simplexLater Onset>7 DaysNeisseria meningitidis
12 NeonatalRisk FactorsPretermMembrane rupture: before labor onset or prolonged>12 hoursChorioamnionitis or maternal peripartum feverUTIMultiple pregnancyHypoxia or Apgar score <6Poverty or age <201/3-1/2 neonatal sepsis will have no risk factors!
13 NeonatalScreening tests: WBC<5000 or >20,000, PMN <4000, I:T>.2, Plt<100,000, CRP>1, LFTs elevated(suggest HSV)So, if <28 days of age and rectal temp> 38ºCAdmitBlood CultureUrine Culture—cath specimenLumbar PunctureCell count, protein, glucose, culture, PCRParenteral AntibioticsAmpicillin + Gentamicin(Cefotaxime), consider Acyclovir(primary maternal infxn, esp if delivered vaginally, PROM, fetal scalp electrodes, skin eye or mouth lesions, seizures, CSF pleocytosis)
14 Infants 1 to 3 months Causes HSV(17% are 15 days to 6 weeks of age)Bacterial sepsis/meningitisGroup B Strep, S. Pneumoniae, H. influenza, N. meningitidis, EnterobacteriaceaeBone and joint infectionsUTIBacterial enteritis(esp Salmonella)PneumoniaEnterovirus sepsis/meningitis(July-October)The risk of bacteremia/meningitis is 3.3%, pneumonia, bone/joint infections and bacterial enteritis is 13.7%30-50% of those who are ultimately diagnosed with bacterial meningitis have been seen by a physician within the prior week(usually 1-2 days before) and were diagnosed as having a trivial illness and discharged on oral antibiotics.These children may have had early meninigitis that was missed or occult bacteremia that progressed to meningitis.
17 Infants 1 to 3 monthsInfants who are toxic and febrile have a much higher risk of serious bacterial infection. They should be admitted, have a full sepsis workup, and given antibiotics/antiviralsAmpicillin and Cefotaxime.Infants who are nontoxic and febrile who meet all Rochester criteria can ‘safely’ be treated as an outpatient. Generally, 1-2.9% of children meeting these criteria will develop a serious bacterial infection, 0.7% bacteremia, 0.14% meningitis.
18 Infants 1 to 3 months Rochester Criteria/Low Risk Criteria Nontoxic—most critical and difficultPreviously healthy, not low birth weightNo focal bacterial infection on PE except Otitis MediaWBC 5,000-15,000/mm3 (normal)Bands<1500/mm3 (normal)Normal urinalysis, including gram stainIf diarrhea, must be non-bloody and WBC<5/hpf.If respiratory symptoms present, normal CXRNegative predictive value 98.9%
19 Infants 1 to 3 monthsIf all of the criteria are met, then there are 2 options for outpatient management:1) Blood, Urine Cultures, LP, Ceftriaxone 50mg/kg IM (to 1g), and return for reevaluation within 24 hours.2) Blood, Urine Cultures and careful observation.Parents should have mature judgement, can return within 30 minutes and have a thermometer and a phone.IF NO LP IS DONE, DO NOT GIVE CEFTRIAXONE AS IT WILL COMPROMISE F/U IF THE PATIENT IS STILL FEBRILE
20 Infants 1 to 3 months Follow-up of low risk infants If all cultures negative: afebrile, well appearingCareful observationBlood cultures negative: well appearing, febrileCareful observation, may consider second dose of CeftriaxoneBlood culture positiveadmit for sepsis workup and parenteral antibiotics pending resultsUrine culture positive: if persistent feveradmit for sepsis workup, parenteral antibiotics pending results. If afebrile and welloutpatient antibiotics
21 Heptavalent pneumococcal conjugate vaccine, PCV7(Prevnar) Licensed in February 2000Routinely incorporated into the childhood immunization schedule in mid-20004, 6B, 9V, 14, 18C, 19F, 23FRecommended for all children aged 2 to 23 monthsInvasive pneumococcal disease in children younger than 2 years has decreased by at least 60%.
23 Rates of Invasive Pneumococcal Disease by Age Group and Year The mean rate of IPD decreased0-30 days 39%31-60 days 45%61-90 days 32%The rate of IPD among infants aged 0 to 60days decreased from 7.3 per 100,000 to 4.2 per 100,000
24 Rates of Invasive Pneumococcal Disease Caused by PCV7 and Non-PCV7 Serotypes in Neonates and Young Infants Aged 0 to 90 Days by Study YearMean rate 7.3 to 2.4
25 So what?This data is the first to suggest that neonates and infants too young to receive PCV7 are benefiting from herd immunity.One hypothesis is that vaccinated children are less likely to have nasal carriage of pneumococcus.
26 Infants 3 to 36 months Infant sepsis syndrome: Age 3-36 monthsFever>39ºCANC>10,000If a child meets all 3 criteria, he has a 3% risk for pneumococcemia. If untreated, 3% will progress to meningitis.Bacteremia risk peaks at 8-12 monthsPneumococcal sepsis peaks at 1 year, then drops offPneumococcal meningitis peaks at 3-5 monthsOM, sinusitis, pneumonia, response to antipyretics, and social status do not significantly alter risk.Other causes: HHV6(15%), UTI(girls 3%, boys 0.6%), menigococcemia(0.1%), Salmonella(0.2%), H. influenza(0.05%), Enterovirus(JulyOctober).
27 Infants 3 to 36 monthsUA with micro, CBC with differential, Blood CulturesLP if meningeal signs, not wanting to be held or moved, petechiae, purpura or toxic.Antimicrobials:OM or pneumonia: cover for pneumococcus, non-typable H. flu and Moraxella: amoxicillin+augmentin, ceftriaxoneURI or no focus: cover for pneumococcus and menigococcus: amoxicillin(80-100mg/dg/day), ceftriaxonePneumococcemia: promptly reassess, if well, should at least treat with 1 dose ceftriaxone.PCV-7 >97% protection, thus all pneumococcal sepsis will decrease by 90%. So CBC and antimicrobials for this age group is becoming less critical.Toxicity assessment: loss of alertness, decreased activity, irritability, higher fever, sustained fever, anorezia, vomiting, pallor, grunting, and maternal worry.
28 Occult Bacteremia 5% of children with FWS have OCCULT BACTEREMIA The presence of a positive blood culture in kids who look well enough to be treated as outpatients and in whom the positive results are not anticipated.
29 Occult BacteremiaStreptococcus pneumonia is responsible for 2/3 to ¾ of all cases.Peak prevalence between 6 and 24 monthsAssociation with high fever(39.4ºC or 103ºF)High WBC count(>15,000)Absence of evident focal soft tissue infection.Neisseria meningitidis, Haemophilus influenzae type b, and salmonellae account for most of the remaining cases.
30 Risk of Occult Bacteremia Low RiskAge >3yrTemp <39.4ºCWBC >5000 and <15,000High Risk<2yr>40ºC(104ºF)<5000 or >15,000Hx of contact with H. Flu or N. meningitidisOB has a low prevalence, so even though WBC is a sensitive and specific screening test, it has a low PPV. So the test does not discriminate between children who have FWS who are bacteremic and those who are not.Therefore, blood culture is the gold standardstill has a high number of false positives, take 24-48hrs, and most cases of occult pneumococcal bacteremia clear without treatment.
31 Occult BacteremiaEmpiric antibiotics should be targeted against S. pneumoniae, N. meningitidis, and H. influenzaAmoxicillinAugmentin, Bactrim, 2nd or 3rd gen CephalosporinsSingle dose Ceftriaxone 50-75mg/kgFollowup is essential!
32 Oski’s Pediatrics, 3rd edition Harriet Lane, 16th editionFWS in Children 0-36 months of age. TCNA 53(2006)The Febrile Child. Emergency Medicine Reports. September 1995.Antibiotic Choices: The critical first hour. Pediatric Annals. June 1996.Evidence based approach to the febrile infant/child. Handout from Dr. Michael Cooperstock, MD. May 2000.Advisory Committee on Immunization Practices. Preventing pneumococcal disease among infants and young children: recommendations of the Advisory Committee on Immunization Practices. MMWR Recomm Rep ;49(RR-9):1-35AAP; Committee on Infectious Disease. Policy statement: recommendations for the prevention of pneumococcal infections, including the use of pneumococcal conjugate vaccine, pneumococcal polysaccharide vaccine, and antibiotic porphylaxis/ Pediatrics. 2000;106:Whitney CG, FarleyMM, Hadler J, et al. Decline in invasive pneumococcal disease after the introduction of protein-polysaccharide vaccine. NEnglJMed ;348:Poehling KA etal. Invasive Pneumococcal Disease Among Infants before and after Introductions of Pneumococcal Conjugate Vaccine. JAMA Apr 12, 2006,295: